Effect of Olmesartan on the Level of Oral Cancer Risk Factor PAI1

To study if the angiotensin receptor blocker olmesartan reduces levels of plasminogen activator inhibitor 1 (PAI1), a risk factor for oral cancer, in a mouse model and therefore whether it could be used in the treatment of this malignancy. Twelve transgenic PAI1 mice aged 16-20 weeks were divided in two groups each containing six animals. One group was given olmesartan every day for 30 days in drinking water in an amount corresponding to their weight, 0.005 mg/g, while the second group did not receive any medication (control group). Blood samples were obtained from animals of both groups, before and after one month of olmesartan administration and plasma PAI1 levels were measured using enzyme-linked immunosorbent assay. In the olmesartan-treated group, a significant decrease of PAI1 level was found after 1 month of treatment (11.9±8.6 vs. 21.7±7.2 ng/ml, respectively; p=0.028). However, no statistically significant difference was observed in PAI1 levels between the olmesartan-treated and control groups after one month, (p=0.177). Olmesartan did not significantly affect PAI1 levels in this mouse model.